Hey Nene.

Well, part of the reason was because I couldn't for the life of me draw myself as a human. But, as part of a flash-project (which never came to be), I decided to design myself as a mutant dinosaur of sorts if I got angry. I based it on the dinosaur family of "Dromeosaurs", or "Raptors" as they are better known...and at the time, there was a really big one called "Megaraptor". So, as a result, I figured that I, in my mutant form, was a Megaraptor.
In time, the Megaraptor form became my only form. And when it was discovered that Megaraptor was an entirely different dinosaur altogether, instead of changing it to the next Raptor down (Utahraptor), I just went with it.

Megaraptor in its actual form is very underappriciated.